The present invention relates to motion sensing devices and more specifically to a device which continuously measures the movement of an infant to determine whether the infant has stopped moving in order to stimulate the infant to resume motion if, in fact, the infant has stopped moving.
Many parents lose sleep for the first several months of an infant""s life. The loss of sleep may be caused by the need to care for the infant""s needs, worry about the infant""s health or safety, or any of a number of other reasons. Many parents place the infant in a bassinet or crib in their own room so that they are better able to respond to any need the infant may have. It is not uncommon for a parent to wake up in the night and place a hand on their sleeping infant""s chest or abdomen to make sure the infant is moving. When motion is sensed or detected, the parent is reassured that the infant is sleeping peacefully. The parent may then resume his or her own peaceful sleep.
In the prior art, many different types of motion sensing devices have been developed for this purpose. One such device is disclosed in Teodorescu et al. U.S. Pat. No. 6,011,477 which discloses a movement monitoring system. The system includes a pair of sensors operably connected to a controller. The sensors are positioned within a mattress that is placed in contact with the infant and determine the amount of movement of the infant over a specified period of time. Signals illustrating the movement of the infant, or lack thereof, are periodically sent from the sensors to the controller for analysis. If the controller determines that the signals from the sensors illustrate that the infant is not moving, the controller then initiates an alarm depending upon the particular condition sensed by the sensors.
Another motion or position sensing device is disclosed in Mesibov et al. U.S. Pat. No. 5,914,660. In this device, a position sensing apparatus is attached to the infant that is to be monitored. The position sensing device then emits a signal which is received by a transceiver to monitor the condition of the infant. The transceiver then transmits the signal to a controller for analysis. If the controller receives a signal which indicates that the infant is no longer moving, the controller can emit a local or a general alarm signal to startle and awake the infant or notify another individual, such as a parent or babysitter in a separate location.
Still another motion sensing device is disclosed in Miller U.S. Pat. No. 5,796,340. In this device, a sensor disposed in a mattress monitors the motion of an individual sleeping on the mattress. The sensor is normally a pressure transducer, such as an electric condenser microphone, which receives and transmits signals indicating the movement of the individual on the mattress. If no signals are transmitted by the sensor during a predetermined period of time, the device then activates an alarm to indicate the non-movement condition to another individual or to stimulate motion by the individual sleeping on the mattress.
One final device used to sense motion or the lack thereof is disclosed in Scanlon U.S. Pat. No. 5,515,865. In this device, a fluid-filled sensor pad is positioned beneath an infant to measure pressure variations created by movement by the infant on the pad. The pressure variations are transmitted as signals to a monitor which determines whether the signals indicate motion or noise created by the infant that exceeds a specified threshold value. If the signals do not exceed the threshold value, the device will attempt to awaken or induce motion by the infant using vibrations, sound and/or lights. If signals exceeding the threshold are still not received, the device will initiate an alarm to notify an individual in a separate location from the infant of the lack of motion condition.
While each of the above-mentioned devices is useful in monitoring the movement of an infant, each of these devices includes a number of separate parts to the device which must be properly connected and/or positioned with respect to one another to ensure the proper operation of the device. The connection and placement of the separate parts of each of these devices greatly increases the complexity and the cost of the devices, making devices of this type prohibitively expensive for many individuals. Furthermore, with the multiple connections needed between the respective parts of each device, the possibility for damaging and/or misconnecting the parts to one another increases.
Therefore, it is desirable to develop a simple, low cost device for monitoring lack of movement of an infant which can be easily utilized by any number of individuals without the need for connecting a number of parts to the device or properly positioning the parts of the device about or to the infant.
It is an object of the present invention to provide a one piece infant movement monitoring and alarm device capable of sensing the lack of movement of an infant and providing an alarm in response to that sensed condition.
It is another object of the invention to provide a device that can be easily attached to the clothing of the infant in order to accurately sense a lack of motion condition.
It is still another object of the invention to provide an infant movement monitoring and alarm device that is easily operable and does not require multiple electrical connections to be made between separate parts of the device.
It is still a further object of the invention to provide a device that has a simple construction enabling the device to be manufactured and sold at a low cost.
The present invention is a movement monitoring and alarm device that can be used to detect the lack of motion of an infant. The confidence a parent gains in the detection of a lack of motion will allow the parent to sleep more soundly. The parent may no longer feel it is necessary to verify that an infant is moving by placing a hand on the chest of the infant.
The device has a unitary housing which encloses all of the sensing and actuating parts of the device. The housing also includes an external securing means attached to the exterior of the housing that is utilized to secure the device to the infant, such as by attaching the device to the clothing of the infant.
Within the interior of the housing, the device includes an accelerometer capable of sensing the movement of the infant to which the device is attached. The accelerometer is formed as a monolithic integrated circuit chip that incorporates a mechanical sensor and electronic signal conditioning circuitry on the chip. The chip is connected to an analyzer or controller which receives the output signal from the accelerometer and determines whether a lack of motion condition exists based on the output signal from the accelerometer. If the output signal is representative of a lack of motion condition for an extended period of time, the controller will initiate an alarm condition and activate an audible signal generator, such as a buzzer, to which the controller is also connected.
By activating the buzzer when a lack of motion condition is sensed by the accelerometer, the device will attempt to startle the infant into motion. However, if the alarm condition persists due to a continued lack of motion of the infant, the noise generated by the buzzer will cause a caregiver to check on the infant and determine the cause of the lack of motion. Once the device detects motion by the infant, the device will deactivate the buzzer and the alarm condition.
Various alternative embodiments and modifications to the invention will be made apparent to one of ordinary skill in the art by the following detailed description taken together with the drawings.